Expansible piston packing



May 5, 1925. I 1,536,426

v G. C. DEAKINS ET AL EXPANSIBLE PISTON PACKING Fi led Oct. 19, 1922 650mm" Ci Dear/a375, Ze/ 12d 6, Biz/fie 2,

'Patented May 5, 1925.

UNITED STATES ,pnfrENT O F F l C E GBOVER G. DEAR-INS, F ANAHEIM, ANDLELAND S. BAKER, 0F FULLERTON, CALI- IORNIA, ASSIGNORS OF ONE-THIRD 1'0ELIHU C. WILSON, 01 LOS ANGELES, CALL FOB-NIL EXPANSIBLE PISTON PACKING.

Application filed October 19, 1822. Serial No. 595,694.

To all whom it may concem:

Be it known that we, Gnovnn C. DEAKINB and LELAND S. HAMER, citizens ofthe United States, and residents of Anaheim and Fullerton, respectively,both in the county of Orange, State of California, have invented new anduseful Improvements in Expansible Piston Packing, of which the followingis a detailed specification.

This invention has to do with packing means for pistons of the generalcharacter used in pumps, compressors, and similar machines, and it is anobject of this invention to provide a simple, effective, improved meansof this character.

An object of the present invention is to provide an arrangement andproportioning of the parts of a simple, efi'ective, automatic pistonpacking means, which permits of quick and convenient assembling.

Another object of this invention is to provide a compact automaticpiston packing means with a wide range of operation or adjustment.

,The various objects and features of our invention will be best and morefully understood by reference to the following detailed description whentaken in connection with the accompanying drawings of one specificembodiment of the invention, while the 'scope of our invention will bemore particu' larly pointed out in the appended claims.

In the drawings Fig. l is a detail sectional view of a pump cylinder andpiston, the piston being constructed in accordance with the presentinvention; and, Fig. 2 is a transverse sectional view of the parts shownin Fig. 1, being a view taken as indicated by line 22 of Fig. 1.

In the drawings numeral designates,

generally, a typical pump cylinder and numeral 11 designates, generally,a piston adapted to operate in the cylinder 10. The cylinder 10 is ofordinary construction and is provided at its outer end with a removablecylinder head 12. The piston 11 is shown arranged in the cylinder andmounted on the outer end of the usual piston rod 13.

In accordance with the present invention the piston 11 is carried on thereduced outer end portion 14 of the piston rod 13 and comprises,generally, an inner end plate 15, an outer end plate 16, a spacer sleeve17 carried on the reduced part 14 between the plates 15 and 16, a bodyof expansible packing 18 carried between the periphery por-' tlons ofthe plates 15 and 16 so that 1t contacts with the wall of the cylinder10, an expansible carrier 19 for the body of packmg 18 and an operatingmechanism 20 adapted to automatically expand the carrier 19 to keep thepacking 18 expanded into proper engagement with the wall of the cylinder10.

The inner end plate 15 is provided with an inwardly extending hub part21 and a. perlphery part 22, which fits the cylinder 10 with clearance.The hub 21 of the plate 15 is screw-threaded onto the inner end portionof the reduced portion 14 until it bears against the shoulder 23 formedon the piston rod between the main portion thereof and the reducedportion 14. A central recess 24 is provided in the inner face of theplate 15 and extends into the hub portion 21. The 7 recess 24 is adaptedto receive a part of the operating mechanism as will be hereinafter morefully described.

The outer end plate 16 is provided with an outwardly extending hub part25 which is slidably carried on the outer and part of the reducedportion 14 and a periphery part 26 which fits the cylinder 10 withclearance. A central recess 27 is provided in the inner face-of theplate 16 and extends into the hub 8 25. The recess is adapted to carry aportion of the operating mechanism 20, as will be hereinafter described.The outer plate 15 is retained on the reduced portion 14 of the pistonrod by means of suitable nuts 28 screwthreaded onto the outer end of thereduced portion 21, as clearly illustrated in Fig. 1 of the drawings.

The spacer sleeve 17 is slidably carried on the reduced portion 14 ofthe piston rod be- 9 tween theplates 15 and 16 and serves to definitelyspace the plates. In practice the nuts 28 are tightened against theplate 16 so that the spacer sleeve 17 is clamped tightly between theplates 15 and 16. 1

The body 18 of packing material is confined between the-peripheryportions of the plates 15 and 16 and is expansible or capable of beingexpanded or forced outwardly to compensate for wear which takes placebe- 1 tween it and the wall of the cylinder. 10. The exact constructionof the body of packing 18 and the exact material out of which the bodyof packing is formed,.- WilLilOf which the pump is to operate and may ineach instance be such as to best suit the existing conditions.

The expansible carrier 19 which I have illustrated in the drawingscomprises a plurality of separate segments 30 which fit toether to forman annular expansible body fiavin a central tapered opening 31 througit. T e several segments 30 are preferably of equal size and of the sameshape so that they form an annular body which can be ex anded uniformlyin all directions.

The outer surfaces of the segments 30 are provided with registeringcircumferential grooves 40 which carry a looped spring 41. The spring41, which is preferably a looped helical spring, serves to yieldinglyhold the segments 30 together so that they form an annular body and sothat they can be conveniently handled when the piston is beingassembled. In accordance with the preferred form of the invention lugs44 extend from the inner face of the plate 15 into radial grooves 45formed in the ends of the segments 30. The lugs 44 cooperate with thegrooves 45 to prevent circumferential movement of the segments but toallow them to be freely movable radially. In practice it is desirable toarrange an ended sheet metal ring 50 between the segments 30 and thepacking 18, as we have clearly illustrated in the drawing. In practicewe prefer to form the ring 50 of sheet metal and to overlap its ends aswe have illustrated in Fig. 2.

The operating mechanism 20 includes a conical wedge member 60 slidablycarried on the sleeve 17 so that it fits the tapered opening 31 in thebody formed by the segments 30 and a spring 51 carried on the sleeve 17between the conical wedge member 50 and the outer end plate 15. Theconical wedge member 15 is shaped or tapered so that its outer surfacecorresponds to and accurately fits the inner surfaces of the segments 30as we have clearly illustrated in the drawings. The spring 51, which isa helical compression spring, extends into the recess 27 in the hub 25of the plate 16 and into a recess 65 which extends deeply into theconical wedge member from its large end. By recessing the plate 16 andalso the conical wedge member as we have illustrated in the drawings aneat compact construction is ob tained and the spring 51 may becomparatively long. The parts are arranged and proportioned so that thelarge end of the conical wedge member 50 extends somewhat into therecess 27 in plate 16 during the first part of the operation of thewedge member, or when the body of packing 18 is comparatively thick, aswe have illustrated in Fig. 1 of the drawings, while its small endextends into the recess in the plate 15 during the last part of theoperation of the Wedge member, or when the body of packing has wornthin. The spring 61 is designed and proportioned so that it iscompressed when in place as illustrated in Fig. 1 and so that it tendsto move the conical wed e member 50 through the opening 31 and-t erebyexpand the carrier 19 and force the packing into enga emcnt with thewall of the cylinder wit substantially uniform pressure during thewearing away of the packing.

From the foregoing description it will be obvious how the pistonprovided by the invention can be easily and quickly assembled or takenapart when the cylinder head 12 is removed and how the operating means20 will operate to automatically feed the packing 18 to compensate forthe wear which takes place between the cylinder wall and the packing. Toassemble the piston the inner end plate is first screw threaded on thereduced portion of the piston rod until it bears against the shoulder onthe rod. The body of packing and the packing carrier are then arrangedin place with relation to the inner end plate so that the lugs 44 extendinto the radial grooves 45. The wedge member and spring are thenarranged on the sleeve 17 and the outer end plate and the nuts 28 arearranged on the end of the reduced portion of the rod. As the nuts aretightened on the end of the reduced portion the spring is compressed andthe outer end plate is moved inwardly until it engages the spacersleeve. When the piston is being taken apart the spring moves the outerend plate outwardly but the other parts remain in place until moved bythe operator. From inspection of the drawings and from the foregoingdescription it will be seen that the arrangement and design of the partsprovided by the present invention is simple and compact at the same timegiving a very wide range of operation to the operating means 30 so thatit will effectively feed a very thick body of packing.

Having described only a typical preferred form of our invention we donot wish to limit ourselves to the particular details hereinabove setforth but wish to reserve to ourselves any changes or variations thatmay appear to those skilled in the art or fall within the scope of thefollowing claims.

Having described a preferred form of my invention, I claim:

1. In combination, a piston rod, two plates on the piston rod, meansspacing the plates apart, each plate having a recess in its inner face,packing carried between the peripheral portions of the plates, and meansfor automatically expanding the packing including, a conical wedgemember with a recess in its large end, the wedge member being slidablelongitudinally on the rod and adapted during the first part of itsoperation to have one end extend into the recess in one of the platesand during the last part of its operation to have its other end extendinto the recess in the other plate, and a compression spring for movingthe wedge member longitudinally, the spring having one and extendinginto the recess in the wedge member and having its other end extendinginto the recess in the plate adjacent the large end of the wedge member.

2. In combination, a iston rod, two plates on the end portion of t erod, the innermost plate being screw threaded on the rod, the outermostplate being slidable on the rod, a sleeve on the rod to space the platesapart, a nut screw threaded on the end of the rod to clamp the outermostplate against the sleeve, each plate having a hub extending from itsouter face and having a recess in its inner face extending into the hub,packing carried between the peripheral portions of the plates, an.expansible annular body inside of the packing, the body including aplurality of separate segments each having a radial groove in. one end,a plurality of lugs extending from the inner face of one of the platesinto the grooves, a conical wedge member slidably carried on the sleeveand adapted to expand said body to feed the packing outwardly, the wedgemember having one end extending into the recess in one of the plateswhen at one end of its movement and having its other end extending intothe recess in the other plate when at the other end of its movement, thewedge member having a. recess in its large end, and a compression springfor operating the wedge member, the spring having one end extending intothe recess in the wedge memher and having its other end extending intothe recess in the plate adjacent the large end of the wedge member.

In witness that we claim the foregoing we have hereunto subscribed ournames this 11th day of October, 1922.

GROVER C. DEAKIN S. LELAND S. HAMIER;

